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Koller F, Plaschke F, Temmer M, Preisser L, Roberts OW, Vörös Z. Magnetosheath Jet Formation Influenced by Parameters in Solar Wind Structures. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2023JA031339. [PMID: 38440351 PMCID: PMC10909547 DOI: 10.1029/2023ja031339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/16/2023] [Accepted: 03/23/2023] [Indexed: 03/06/2024]
Abstract
Magnetosheath jets are dynamic pressure enhancements observed in the terrestrial magnetosheath. Their generation mechanisms are currently debated but the majority of jets can be linked to foreshock processes. Recent results showed that jets are less numerous when coronal mass ejections (CMEs) cross the magnetosheath and more numerous when stream interaction regions (SIRs) cross it. Here, we show for the first time how the pronounced substructures of CMEs and SIRs are related to jet production. We distinguish between compression and magnetic ejecta (ME) regions for the CME as well as compression region associated with the stream interface and high-speed streams (HSSs) for the SIR. Based on THEMIS and OMNI data covering 2008-2021, we show the 2D probability distribution of jet occurrence using the cone angle and Alfvén Mach number. We compare this distribution with the values within each solar wind (SW) structure. We find that both high cone angles and low Alfvén Mach numbers within CME-MEs are unfavorable for jet production as they may inhibit a well-defined foreshock region. 1D histograms of all parameters show, which SW parameters govern jet occurrence in each SW structure. In terms of the considered parameters the most favorable conditions for jet generation are found for HSSs due to their associated low cone angles, low densities, and low magnetic field strengths.
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Affiliation(s)
| | - Ferdinand Plaschke
- Institut für Geophysik und Extraterrestrische PhysikTU BraunschweigBraunschweigGermany
| | | | - Luis Preisser
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Owen W. Roberts
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Zoltan Vörös
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of Earth Physics and Space ScienceELRNSopronHungary
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2
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Koller F, Temmer M, Preisser L, Plaschke F, Geyer P, Jian LK, Roberts OW, Hietala H, LaMoury AT. Magnetosheath Jet Occurrence Rate in Relation to CMEs and SIRs. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2022; 127:e2021JA030124. [PMID: 35866074 PMCID: PMC9286365 DOI: 10.1029/2021ja030124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/17/2022] [Accepted: 03/23/2022] [Indexed: 06/15/2023]
Abstract
Magnetosheath jets constitute a significant coupling effect between the solar wind (SW) and the magnetosphere of the Earth. In order to investigate the effects and forecasting of these jets, we present the first-ever statistical study of the jet production during large-scale SW structures like coronal mass ejections (CMEs), stream interaction regions (SIRs) and high speed streams (HSSs). Magnetosheath data from Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft between January 2008 and December 2020 serve as measurement source for jet detection. Two different jet definitions were used to rule out statistical biases induced by our jet detection method. For the CME and SIR + HSS lists, we used lists provided by literature and expanded on incomplete lists using OMNI data to cover the time range of May 1996 to December 2020. We find that the number and total time of observed jets decrease when CME-sheaths hit the Earth. The number of jets is lower throughout the passing of the CME-magnetic ejecta (ME) and recovers quickly afterward. On the other hand, the number of jets increases during SIR and HSS phases. We discuss a few possibilities to explain these statistical results.
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Affiliation(s)
| | | | - Luis Preisser
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Ferdinand Plaschke
- Institut für Geophysik und extraterrestrische PhysikTU BraunschweigBraunschweigGermany
| | - Paul Geyer
- Institute of PhysicsUniversity of GrazGrazAustria
- Hvar Observatory, Faculty of GeodesyUniversity of ZagrebZagrebCroatia
| | - Lan K. Jian
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Owen W. Roberts
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Heli Hietala
- The Blackett LaboratoryImperial College LondonLondonUK
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3
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Nitta NV, Mulligan T, Kilpua EKJ, Lynch BJ, Mierla M, O’Kane J, Pagano P, Palmerio E, Pomoell J, Richardson IG, Rodriguez L, Rouillard AP, Sinha S, Srivastava N, Talpeanu DC, Yardley SL, Zhukov AN. Understanding the Origins of Problem Geomagnetic Storms Associated with "Stealth" Coronal Mass Ejections. SPACE SCIENCE REVIEWS 2021; 217:82. [PMID: 34789949 PMCID: PMC8566663 DOI: 10.1007/s11214-021-00857-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
Geomagnetic storms are an important aspect of space weather and can result in significant impacts on space- and ground-based assets. The majority of strong storms are associated with the passage of interplanetary coronal mass ejections (ICMEs) in the near-Earth environment. In many cases, these ICMEs can be traced back unambiguously to a specific coronal mass ejection (CME) and solar activity on the frontside of the Sun. Hence, predicting the arrival of ICMEs at Earth from routine observations of CMEs and solar activity currently makes a major contribution to the forecasting of geomagnetic storms. However, it is clear that some ICMEs, which may also cause enhanced geomagnetic activity, cannot be traced back to an observed CME, or, if the CME is identified, its origin may be elusive or ambiguous in coronal images. Such CMEs have been termed "stealth CMEs". In this review, we focus on these "problem" geomagnetic storms in the sense that the solar/CME precursors are enigmatic and stealthy. We start by reviewing evidence for stealth CMEs discussed in past studies. We then identify several moderate to strong geomagnetic storms (minimum Dst < - 50 nT) in solar cycle 24 for which the related solar sources and/or CMEs are unclear and apparently stealthy. We discuss the solar and in situ circumstances of these events and identify several scenarios that may account for their elusive solar signatures. These range from observational limitations (e.g., a coronagraph near Earth may not detect an incoming CME if it is diffuse and not wide enough) to the possibility that there is a class of mass ejections from the Sun that have only weak or hard-to-observe coronal signatures. In particular, some of these sources are only clearly revealed by considering the evolution of coronal structures over longer time intervals than is usually considered. We also review a variety of numerical modelling approaches that attempt to advance our understanding of the origins and consequences of stealthy solar eruptions with geoeffective potential. Specifically, we discuss magnetofrictional modelling of the energisation of stealth CME source regions and magnetohydrodynamic modelling of the physical processes that generate stealth CME or CME-like eruptions, typically from higher altitudes in the solar corona than CMEs from active regions or extended filament channels.
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Affiliation(s)
- Nariaki V. Nitta
- Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 USA
| | - Tamitha Mulligan
- Space Sciences Department, The Aerospace Corporation, Los Angeles, CA 94305 USA
| | | | - Benjamin J. Lynch
- Space Sciences Laboratory, University of California–Berkeley, Berkeley, CA 94720 USA
| | - Marilena Mierla
- Solar–Terrestrial Centre of Excellence—SIDC, Royal Observatory of Belgium, 1180 Brussels, Belgium
- Institute of Geodynamics of the Romanian Academy, 020032 Bucharest-37, Romania
| | - Jennifer O’Kane
- Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT UK
| | - Paolo Pagano
- School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9SS UK
- Dipartimento di Fisica & Chimica, Università di Palermo, I-90134 Palermo, Italy
- INAF–Osservatorio Astronomico di Palermo, I-90134 Palermo, Italy
| | - Erika Palmerio
- Department of Physics, University of Helsinki, FI-00014 Helsinki, Finland
- Space Sciences Laboratory, University of California–Berkeley, Berkeley, CA 94720 USA
- Cooperative Programs for the Advancement of Earth System Science, University Corporation for Atmospheric Research, Boulder, CO 80301 USA
| | - Jens Pomoell
- Department of Physics, University of Helsinki, FI-00014 Helsinki, Finland
| | - Ian G. Richardson
- Department of Astronomy, University of Maryland, College Park, MD 20742 USA
- Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA
| | - Luciano Rodriguez
- Solar–Terrestrial Centre of Excellence—SIDC, Royal Observatory of Belgium, 1180 Brussels, Belgium
| | - Alexis P. Rouillard
- IRAP, Université Toulouse III—Paul Sabatier, CNRS, CNES, 31400 Toulouse, France
| | - Suvadip Sinha
- Centre of Excellence in Space Sciences India, Indian Institute of Science Education and Research, Kolkata, Mohanpur, 741246 India
| | - Nandita Srivastava
- Centre of Excellence in Space Sciences India, Indian Institute of Science Education and Research, Kolkata, Mohanpur, 741246 India
- Udaipur Solar Observatory, Physical Research Laboratory, Udaipur, 313001 India
| | - Dana-Camelia Talpeanu
- Solar–Terrestrial Centre of Excellence—SIDC, Royal Observatory of Belgium, 1180 Brussels, Belgium
- Centre for Mathematical Plasma Astrophysics (CmPA), KU Leuven, 3001 Leuven, Belgium
| | - Stephanie L. Yardley
- Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT UK
- School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9SS UK
| | - Andrei N. Zhukov
- Solar–Terrestrial Centre of Excellence—SIDC, Royal Observatory of Belgium, 1180 Brussels, Belgium
- Skobeltsyn Institute of Nuclear Physics, Moscow State University, 119991 Moscow, Russia
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Palmerio E, Nieves‐Chinchilla T, Kilpua EKJ, Barnes D, Zhukov AN, Jian LK, Witasse O, Provan G, Tao C, Lamy L, Bradley TJ, Mays ML, Möstl C, Roussos E, Futaana Y, Masters A, Sánchez‐Cano B. Magnetic Structure and Propagation of Two Interacting CMEs From the Sun to Saturn. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2021; 126:e2021JA029770. [PMID: 35864948 PMCID: PMC9286593 DOI: 10.1029/2021ja029770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/01/2021] [Accepted: 10/05/2021] [Indexed: 06/15/2023]
Abstract
One of the grand challenges in heliophysics is the characterization of coronal mass ejection (CME) magnetic structure and evolution from eruption at the Sun through heliospheric propagation. At present, the main difficulties are related to the lack of direct measurements of the coronal magnetic fields and the lack of 3D in-situ measurements of the CME body in interplanetary space. Nevertheless, the evolution of a CME magnetic structure can be followed using a combination of multi-point remote-sensing observations and multi-spacecraft in-situ measurements as well as modeling. Accordingly, we present in this work the analysis of two CMEs that erupted from the Sun on April 28, 2012. We follow their eruption and early evolution using remote-sensing data, finding indications of CME-CME interaction, and then analyze their interplanetary counterpart(s) using in-situ measurements at Venus, Earth, and Saturn. We observe a seemingly single flux rope at all locations, but find possible signatures of interaction at Earth, where high-cadence plasma data are available. Reconstructions of the in-situ flux ropes provide almost identical results at Venus and Earth but show greater discrepancies at Saturn, suggesting that the CME was highly distorted and/or that further interaction with nearby solar wind structures took place before 10 AU. This work highlights the difficulties in connecting structures from the Sun to the outer heliosphere and demonstrates the importance of multi-spacecraft studies to achieve a deeper understanding of the magnetic configuration of CMEs.
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Affiliation(s)
- Erika Palmerio
- Space Sciences LaboratoryUniversity of California–BerkeleyBerkeleyCAUSA
- CPAESSUniversity Corporation for Atmospheric ResearchBoulderCOUSA
| | | | | | - David Barnes
- STFC RAL SpaceRutherford Appleton LaboratoryHarwell CampusOxfordshireUK
| | - Andrei N. Zhukov
- Solar–Terrestrial Centre of Excellence—SIDCRoyal Observatory of BelgiumBrusselsBelgium
- Skobeltsyn Institute of Nuclear PhysicsMoscow State UniversityMoscowRussia
| | - Lan K. Jian
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - Gabrielle Provan
- School of Physics and AstronomyUniversity of LeicesterLeicesterUK
| | - Chihiro Tao
- National Institute of Information and Communications Technology (NICT)KoganeiJapan
| | - Laurent Lamy
- LESIAObservatoire de ParisPSLCNRSUPMCUniversité Paris DiderotMeudonFrance
- LAMPythéasAix Marseille UniversitéCNRSCNESMarseilleFrance
| | | | - M. Leila Mays
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Christian Möstl
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of GeodesyGraz University of TechnologyGrazAustria
| | - Elias Roussos
- Max Planck Institute for Solar System ResearchGöttingenGermany
| | | | - Adam Masters
- The Blackett LaboratoryImperial College LondonLondonUK
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Zhang J, Temmer M, Gopalswamy N, Malandraki O, Nitta NV, Patsourakos S, Shen F, Vršnak B, Wang Y, Webb D, Desai MI, Dissauer K, Dresing N, Dumbović M, Feng X, Heinemann SG, Laurenza M, Lugaz N, Zhuang B. Earth-affecting solar transients: a review of progresses in solar cycle 24. PROGRESS IN EARTH AND PLANETARY SCIENCE 2021; 8:56. [PMID: 34722120 PMCID: PMC8550066 DOI: 10.1186/s40645-021-00426-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 04/26/2021] [Indexed: 06/13/2023]
Abstract
This review article summarizes the advancement in the studies of Earth-affecting solar transients in the last decade that encompasses most of solar cycle 24. It is a part of the effort of the International Study of Earth-affecting Solar Transients (ISEST) project, sponsored by the SCOSTEP/VarSITI program (2014-2018). The Sun-Earth is an integrated physical system in which the space environment of the Earth sustains continuous influence from mass, magnetic field, and radiation energy output of the Sun in varying timescales from minutes to millennium. This article addresses short timescale events, from minutes to days that directly cause transient disturbances in the Earth's space environment and generate intense adverse effects on advanced technological systems of human society. Such transient events largely fall into the following four types: (1) solar flares, (2) coronal mass ejections (CMEs) including their interplanetary counterparts ICMEs, (3) solar energetic particle (SEP) events, and (4) stream interaction regions (SIRs) including corotating interaction regions (CIRs). In the last decade, the unprecedented multi-viewpoint observations of the Sun from space, enabled by STEREO Ahead/Behind spacecraft in combination with a suite of observatories along the Sun-Earth lines, have provided much more accurate and global measurements of the size, speed, propagation direction, and morphology of CMEs in both 3D and over a large volume in the heliosphere. Many CMEs, fast ones, in particular, can be clearly characterized as a two-front (shock front plus ejecta front) and three-part (bright ejecta front, dark cavity, and bright core) structure. Drag-based kinematic models of CMEs are developed to interpret CME propagation in the heliosphere and are applied to predict their arrival times at 1 AU in an efficient manner. Several advanced MHD models have been developed to simulate realistic CME events from the initiation on the Sun until their arrival at 1 AU. Much progress has been made on detailed kinematic and dynamic behaviors of CMEs, including non-radial motion, rotation and deformation of CMEs, CME-CME interaction, and stealth CMEs and problematic ICMEs. The knowledge about SEPs has also been significantly improved. An outlook of how to address critical issues related to Earth-affecting solar transients concludes this article.
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Affiliation(s)
- Jie Zhang
- Department of Physics and Astronomy, George Mason University, 4400 University Dr., MSN 3F3, Fairfax, VA 22030 USA
| | | | | | - Olga Malandraki
- National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, Penteli, Athens Greece
| | - Nariaki V. Nitta
- Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA USA
| | | | - Fang Shen
- SIGMA Weather Group, State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing, 100190 China
| | - Bojan Vršnak
- Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, HR-10000 Zagreb, Croatia
| | - Yuming Wang
- CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, Anhui 230026 PR China
| | - David Webb
- ISR, Boston College, 140 Commonwealth Ave., Chestnut Hill, MA 02467 USA
| | - Mihir I. Desai
- Southwest Research Institute, 6220 Culebra Road, San Antonia, TX 78023 USA
- Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX 78249 USA
| | - Karin Dissauer
- Institute of Physics, University of Graz, Graz, Austria
- NorthWest Research Association, Boulder, CO USA
| | - Nina Dresing
- Institut fuer Experimentelle und Angewandte Physik, University of Kiel, Kiel, Germany
- Department of Physics and Astronomy, University of Turku, Turku, Finland
| | - Mateja Dumbović
- Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, HR-10000 Zagreb, Croatia
| | - Xueshang Feng
- SIGMA Weather Group, State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing, 100190 China
| | - Stephan G. Heinemann
- Institute of Physics, University of Graz, Graz, Austria
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Monica Laurenza
- INAF-Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere, 100, I-00133 Rome, Italy
| | - Noé Lugaz
- Space Science Center and Department of Physics, University of New Hampshire, Durham, NH USA
| | - Bin Zhuang
- Space Science Center and Department of Physics, University of New Hampshire, Durham, NH USA
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Blum LW, Koval A, Richardson IG, Wilson LB, Malaspina D, Greeley A, Jaynes AN. Prompt Response of the Dayside Magnetosphere to Discrete Structures Within the Sheath Region of a Coronal Mass Ejection. GEOPHYSICAL RESEARCH LETTERS 2021; 48:e2021GL092700. [PMID: 34219832 PMCID: PMC8244059 DOI: 10.1029/2021gl092700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 06/13/2023]
Abstract
A sequence of discrete solar wind structures within the sheath region of an interplanetary coronal mass ejection on November 6, 2015, caused a series of compressions and releases of the dayside magnetosphere. Each compression resulted in a brief adiabatic enhancement of ions (electrons) driving bursts of electromagnetic ion cyclotron (EMIC; whistler mode chorus) wave growth across the dayside magnetosphere. Fine-structured rising tones were observed in the EMIC wave bursts, resulting in nonlinear scattering of relativistic electrons in the outer radiation belt. Multipoint observations allow us to study the spatial structure and evolution of these sheath structures as they propagate Earthward from L1 as well as the spatio-temporal characteristics of the magnetospheric response. This event highlights the importance of fine-scale solar wind structure, in particular within complex sheath regions, in driving dayside phenomena within the inner magnetosphere.
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Affiliation(s)
- L. W. Blum
- Department of Astrophysical and Planetary SciencesCU BoulderBoulderCOUSA
- Laboratory for Atmospheric and Space PhysicsCU BoulderBoulderCOUSA
| | - A. Koval
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- University of Maryland Baltimore CountyBaltimoreMDUSA
| | - I. G. Richardson
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | | | - D. Malaspina
- Department of Astrophysical and Planetary SciencesCU BoulderBoulderCOUSA
- Laboratory for Atmospheric and Space PhysicsCU BoulderBoulderCOUSA
| | - A. Greeley
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - A. N. Jaynes
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
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7
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Wilson LB, Brosius AL, Gopalswamy N, Nieves‐Chinchilla T, Szabo A, Hurley K, Phan T, Kasper JC, Lugaz N, Richardson IG, Chen CHK, Verscharen D, Wicks RT, TenBarge JM. A Quarter Century of Wind Spacecraft Discoveries. REVIEWS OF GEOPHYSICS (WASHINGTON, D.C. : 1985) 2021; 59:e2020RG000714. [PMCID: PMC9285980 DOI: 10.1029/2020rg000714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/29/2021] [Accepted: 03/05/2021] [Indexed: 06/13/2023]
Abstract
The Wind spacecraft, launched on November 1, 1994, is a critical element in NASA’s Heliophysics System Observatory (HSO)—a fleet of spacecraft created to understand the dynamics of the Sun‐Earth system. The combination of its longevity (>25 years in service), its diverse complement of instrumentation, and high resolution and accurate measurements has led to it becoming the “standard candle” of solar wind measurements. Wind has over 55 selectable public data products with over ∼1,100 total data variables (including OMNI data products) on SPDF/CDAWeb alone. These data have led to paradigm shifting results in studies of statistical solar wind trends, magnetic reconnection, large‐scale solar wind structures, kinetic physics, electromagnetic turbulence, the Van Allen radiation belts, coronal mass ejection topology, interplanetary and interstellar dust, the lunar wake, solar radio bursts, solar energetic particles, and extreme astrophysical phenomena such as gamma‐ray bursts. This review introduces the mission and instrument suites then discusses examples of the contributions by Wind to these scientific topics that emphasize its importance to both the fields of heliophysics and astrophysics. Wind has made seminal advances to the fields of astrophysics, turbulence, kinetic physics, magnetic reconnection, and the radiation belts Wind pioneered the study of the source and evolution of solar radio emissions below 15 MHz Wind revolutionized our understanding of coronal mass ejections, their internal magnetic structure, and evolution
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Affiliation(s)
- Lynn B. Wilson
- NASA Goddard Space Flight CenterHeliophysics Science DivisionGreenbeltMDUSA
| | - Alexandra L. Brosius
- NASA Goddard Space Flight CenterHeliophysics Science DivisionGreenbeltMDUSA
- Department of Meteorology and Atmospheric ScienceThe Pennsylvania State UniversityUniversity ParkPAUSA
| | | | | | - Adam Szabo
- NASA Goddard Space Flight CenterHeliophysics Science DivisionGreenbeltMDUSA
| | - Kevin Hurley
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - Tai Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - Justin C. Kasper
- School of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborAnn ArborMIUSA
| | - Noé Lugaz
- Space Science CenterInstitute for the Study of EarthOceans, and SpaceUniversity of New HampshireDurhamNHUSA
- Department of PhysicsUniversity of New HampshireDurhamNHUSA
| | - Ian G. Richardson
- NASA Goddard Space Flight CenterHeliophysics Science DivisionGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | | | - Daniel Verscharen
- Space Science CenterInstitute for the Study of EarthOceans, and SpaceUniversity of New HampshireDurhamNHUSA
- Mullard Space Science LaboratoryUniversity College LondonSurreyUK
| | - Robert T. Wicks
- Department of MathematicsPhysics and Electrical EngineeringNorthumbria University: Newcastle upon TyneTyne and WearUK
| | - Jason M. TenBarge
- University of MarylandCollege ParkMDUSA
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
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8
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Viall NM, Borovsky JE. Nine Outstanding Questions of Solar Wind Physics. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2020; 125:e2018JA026005. [PMID: 32728511 PMCID: PMC7380306 DOI: 10.1029/2018ja026005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 01/15/2020] [Accepted: 01/22/2020] [Indexed: 06/11/2023]
Abstract
In situ measurements of the solar wind have been available for almost 60 years, and in that time plasma physics simulation capabilities have commenced and ground-based solar observations have expanded into space-based solar observations. These observations and simulations have yielded an increasingly improved knowledge of fundamental physics and have delivered a remarkable understanding of the solar wind and its complexity. Yet there are longstanding major unsolved questions. Synthesizing inputs from the solar wind research community, nine outstanding questions of solar wind physics are developed and discussed in this commentary. These involve questions about the formation of the solar wind, about the inherent properties of the solar wind (and what the properties say about its formation), and about the evolution of the solar wind. The questions focus on (1) origin locations on the Sun, (2) plasma release, (3) acceleration, (4) heavy-ion abundances and charge states, (5) magnetic structure, (6) Alfven waves, (7) turbulence, (8) distribution-function evolution, and (9) energetic-particle transport. On these nine questions we offer suggestions for future progress, forward looking on what is likely to be accomplished in near future with data from Parker Solar Probe, from Solar Orbiter, from the Daniel K. Inouye Solar Telescope (DKIST), and from Polarimeter to Unify the Corona and Heliosphere (PUNCH). Calls are made for improved measurements, for higher-resolution simulations, and for advances in plasma physics theory.
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9
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Heinemann SG, Temmer M, Farrugia CJ, Dissauer K, Kay C, Wiegelmann T, Dumbović M, Veronig AM, Podladchikova T, Hofmeister SJ, Lugaz N, Carcaboso F. CME-HSS Interaction and Characteristics Tracked from Sun to Earth. SOLAR PHYSICS 2019; 294:121. [PMID: 31929659 PMCID: PMC6936343 DOI: 10.1007/s11207-019-1515-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
In a thorough study, we investigate the origin of a remarkable plasma and magnetic field configuration observed in situ on June 22, 2011, near L1, which appears to be a magnetic ejecta (ME) and a shock signature engulfed by a solar wind high-speed stream (HSS). We identify the signatures as an Earth-directed coronal mass ejection (CME), associated with a C7.7 flare on June 21, 2011, and its interaction with a HSS, which emanates from a coronal hole (CH) close to the launch site of the CME. The results indicate that the major interaction between the CME and the HSS starts at a height of 1.3 R ⊙ up to 3 R ⊙ . Over that distance range, the CME undergoes a strong north-eastward deflection of at least 30 ∘ due to the open magnetic field configuration of the CH. We perform a comprehensive analysis for the CME-HSS event using multi-viewpoint data (from the Solar TErrestrial RElations Observatories, the Solar and Heliospheric Observatory and the Solar Dynamics Observatory), and combined modeling efforts (nonlinear force-free field modeling, Graduated Cylindrical Shell CME modeling, and the Forecasting a CME's Altered Trajectory - ForeCAT model). We aim at better understanding its early evolution and interaction process as well as its interplanetary propagation and related in situ signatures, and finally the resulting impact on the Earth's magnetosphere.
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Affiliation(s)
- Stephan G. Heinemann
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Manuela Temmer
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Charles J. Farrugia
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Morse Hall, 8 College Road, Durham, NH 03824-3525 USA
| | - Karin Dissauer
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Christina Kay
- Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD USA
- Dept. of Physics, The Catholic University of America, Washington, DC USA
| | - Thomas Wiegelmann
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Mateja Dumbović
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Astrid M. Veronig
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
- Kanzelhöhe Observatory for Solar and Environmental Research, University of Graz, 9521 Treffen, Austria
| | - Tatiana Podladchikova
- Skolkovo Institute of Science and Technology Skolkovo Innovation Center, Building 3, Moscow, 143026 Russia
| | - Stefan J. Hofmeister
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Noé Lugaz
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Morse Hall, 8 College Road, Durham, NH 03824-3525 USA
| | - Fernando Carcaboso
- Dpto. de Física y Matemáticas, Universidad de Alcalá, 28805 Alcalá de Henares, Madrid, Spain
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10
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Pomoell J, Lumme E, Kilpua E. Time-dependent Data-driven Modeling of Active Region Evolution Using Energy-optimized Photospheric Electric Fields. SOLAR PHYSICS 2019; 294:41. [PMID: 31057187 PMCID: PMC6459003 DOI: 10.1007/s11207-019-1430-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 03/15/2019] [Indexed: 06/09/2023]
Abstract
In this work, we present results of a time-dependent data-driven numerical simulation developed to study the dynamics of coronal active region magnetic fields. The evolving boundary condition driving the model, the photospheric electric field, is inverted using a time sequence of vector magnetograms as input. We invert three distinct electric field datasets for a single active region. All three electric fields reproduce the observed evolution of the normal component of the magnetic field. Two of the datasets are constructed so as to match the energy input into the corona to that provided by a reference estimate. Using the three inversions as input to a time-dependent magnetofrictional model, we study the response of the coronal magnetic field to the driving electric fields. The simulations reveal the magnetic field evolution to be sensitive to the input electric field despite the normal component of the magnetic field evolving identically and the total energy injection being largely similar. Thus, we demonstrate that the total energy injection is not sufficient to characterize the evolution of the coronal magnetic field: coronal evolution can be very different despite similar energy injections. We find the relative helicity to be an important additional metric that allows one to distinguish the simulations. In particular, the simulation with the highest relative helicity content produces a coronal flux rope that subsequently erupts, largely in agreement with extreme-ultraviolet imaging observations of the corresponding event. Our results suggest that time-dependent data-driven simulations that employ carefully constructed driving boundary conditions offer a valuable tool for modeling and characterizing the evolution of coronal magnetic fields. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (10.1007/s11207-019-1430-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jens Pomoell
- Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
| | - Erkka Lumme
- Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
| | - Emilia Kilpua
- Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
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11
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Bruno A, Christian ER, de Nolfo GA, Richardson IG, Ryan JM. Spectral Analysis of the September 2017 Solar Energetic Particle Events. SPACE WEATHER : THE INTERNATIONAL JOURNAL OF RESEARCH & APPLICATIONS 2019; 17:419-437. [PMID: 33363448 PMCID: PMC7756961 DOI: 10.1029/2018sw002085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
An interval of exceptional solar activity was registered in early September 2017, late in the decay phase of solar cycle 24, involving the complex Active Region 12673 as it rotated across the western hemisphere with respect to Earth. A large number of eruptions occurred between 4 and 10 September, including four associated with X-class flares. The X9.3 flare on 6 September and the X8.2 flare on 10 September are currently the two largest during cycle 24. Both were accompanied by fast coronal mass ejections and gave rise to solar energetic particle (SEP) events measured by near-Earth spacecraft. In particular, the partially occulted solar event on 10 September triggered a ground-level enhancement (GLE), the second GLE of cycle 24. A further, much less energetic SEP event was recorded on 4 September. In this work we analyze observations by the Advanced Composition Explorer (ACE) and the Geostationary Operational Environmental Satellites (GOES), estimating the SEP event-integrated spectra above 300 keV and carrying out a detailed study of the spectral shape temporal evolution. Derived spectra are characterized by a low-energy break at few/tens of MeV; the 10 September event spectrum, extending up to ~1 GeV, exhibits an additional rollover at several hundred MeV. We discuss the spectral interpretation in the scenario of shock acceleration and in terms of other important external influences related to interplanetary transport and magnetic connectivity, taking advantage of multipoint observations from the Solar Terrestrial Relations Observatory. Spectral results are also compared with those obtained for the 17 May 2012 GLE event.
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Affiliation(s)
- A. Bruno
- Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - E. R. Christian
- Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - G. A. de Nolfo
- Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - I. G. Richardson
- Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Department of Astronomy, University of Maryland, College Park, MD, USA
| | - J. M. Ryan
- Space Science Center, University of New Hampshire, Durham, NH, USA
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